On Fri, Dec 26, 2003 at 19:42:44 -0700, Michael Fuhr <[EMAIL PROTECTED]> wrote: > > I have several databases with lat/lon coordinates and frequently make > "show me all records within a certain distance of this point" queries. > I wrote a haversine() function that uses the Haversine Formula to > calculate the great circle distance between two points on a sphere > (assuming the earth is a perfect sphere is accurate enough for my uses). > Here's a web site with related info:
The distance operator in contrib/earthdistance got changed to use haversine instead of the naive formula in 7.3. In 7.4 it also provides some functions that work with contrib/cube that allow for indexed searches. ---------------------------(end of broadcast)--------------------------- TIP 5: Have you checked our extensive FAQ? http://www.postgresql.org/docs/faqs/FAQ.html